<template>
  <div>
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>

    <el-card>
      <el-alert title="注意: 只允许为三极分类设置相关参数!" type="warning" :closable="false" show-icon></el-alert>

      <!-- 选择商品分类区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类: </span>

          <!-- 选择商品分类的级联选择框 -->
          <el-cascader
            v-model="selectCateKeys"
            :options="cateList"
            :props="{
              expandTrigger: 'hover',
              value: 'cat_id',
              label: 'cat_name',
              children: 'children'
            }"
            @change="handleChange"
          ></el-cascader>
        </el-col>
      </el-row>

      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数按钮 -->
          <el-button @click="addDialogVisible = true" :disabled="isBtnDisabled" type="primary" size="mini">
            添加参数
          </el-button>

          <!-- 动态参数表格 -->
          <el-table :data="manyTabData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染 tag 标签 -->
                <el-tag closable v-for="(item, i) in scope.row.attr_vals" :key="i" @close="handleClosed(i, scope.row)">
                  {{ item }}
                </el-tag>

                <!-- 输入文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>

                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">
                  + New Tag
                </el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button @click="showEditDialog(scope.row.attr_id)" size="mini" type="primary" icon="el-icon-edit">
                  编 辑
                </el-button>

                <el-button @click="removeParams(scope.row.attr_id)" size="mini" type="danger" icon="el-icon-delete">
                  删 除
                </el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>

        <!-- 添加静态属性面板 -->
        <el-tab-pane label="静态参数" name="only">
          <!-- 添加属性按钮 -->
          <el-button @click="addDialogVisible = true" :disabled="isBtnDisabled" type="primary" size="mini">
            添加属性
          </el-button>

          <!-- 静态属性表格 -->
          <el-table :data="onlyTabData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染 tag 标签 -->
                <el-tag closable v-for="(item, i) in scope.row.attr_vals" :key="i" @close="handleClosed(i, scope.row)">
                  {{ item }}
                </el-tag>

                <!-- 输入文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>

                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">
                  + New Tag
                </el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button @click="showEditDialog(scope.row.attr_id)" size="mini" type="primary" icon="el-icon-edit">
                  编 辑
                </el-button>
                <el-button @click="removeParams(scope.row.attr_id)" size="mini" type="danger" icon="el-icon-delete">
                  删 除
                </el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 添加参数对话框 -->
    <el-dialog :title="'添加' + titleText" :visible.sync="addDialogVisible" width="50%" @close="addDialogClosed">
      <!-- 添加参数的对话框 -->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改参数对话框 -->
    <el-dialog :title="'修改' + titleText" :visible.sync="editDialogVisible" width="50%" @close="editDialogClosed">
      <!-- 添加参数的对话框 -->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
import { getCate, getCateAttrById, delCateAttrById, putCateAttrById, getCateById, postCateById } from '@/api/goods'

export default {
  name: 'params',
  data() {
    return {
      // 商品分类列表
      cateList: [],
      // 级联选择框双向绑定到的数组
      selectCateKeys: [],
      // 被激活的页签名称
      activeName: 'many',
      // 动态参数数据
      manyTabData: [],
      // 静态属性数据
      onlyTabData: [],
      // 控制添加对话框的显示与隐藏
      addDialogVisible: false,
      // 添加参数的表单数据对象
      addForm: {
        attr_name: ''
      },
      // 添加表单验证规则对象
      addFormRules: {
        attr_name: [{ required: true, message: '请输入参数名称', trigger: 'blur' }]
      },
      //控制修改对话框的显示与隐藏
      editDialogVisible: false,
      // 修改的表单数据对象
      editForm: {},
      // 修改表单的验证规则对象
      editFormRules: {
        attr_name: [{ required: true, message: '请输入参数名称', trigger: 'blur' }]
      }
    }
  },
  created() {
    this.getCateList()
  },
  methods: {
    // 获取所有的商品分类列表
    async getCateList() {
      const res = await getCate()
      if (res.meta.status === 200) {
        this.cateList = res.data
      } else {
        this.$message.error('获取商品分类失败')
      }
    },
    // 级联选择框选中项变化触发
    handleChange() {
      this.getParamsData()
    },

    // tab 页签点击事件处理函数
    handleTabClick() {
      this.getParamsData()
    },

    // 删除对应的参数可选项
    handleClosed(i, row) {
      row.attr_vals.splice(i, 1)
      this.saveAttr_vals(row)
    },

    // 文本框失去焦点触发
    async handleInputConfirm(row) {
      if (row.inputValue.trim().length === 0) {
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      // 如果没有 return 证明输入了内容 需要后续处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      // 发起请求保存
      this.saveAttr_vals(row)
    },

    // 点击按钮展示文本框
    showInput(row) {
      row.inputVisible = true
      // 让文本框自动获得焦点
      // nextTick 作用：当页面上元素被重新渲染后才执行回调函数中的代码
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },

    // 点击按钮展示修改对话框
    async showEditDialog(attrId) {
      // 查询当前参数的信息
      let params = {
        id: this.cateId,
        attrId: attrId,
        attr_sel: this.activeName
      }
      const res = await getCateAttrById(params)
      if (res.meta.status === 200) {
        this.editForm = res.data
        this.editDialogVisible = true
      } else {
        this.$message.error('获取参数信息失败')
      }
    },

    // 根据 id 删除对应的参数项
    async removeParams(attrId) {
      const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).catch(err => err)
      // 用户取消了删除操作
      if (confirmResult === 'confirm') {
        // 用户点击删除
        let params = {
          id: this.cateId,
          attrId: attrId
        }
        const res = await delCateAttrById(params)
        if (res.meta.status === 200) {
          this.$message.success('删除参数成功')
          this.getParamsData()
        } else {
          this.$message.error('删除参数失败')
        }
      } else {
        this.$message.info('已取消删除')
      }
    },

    // 监听添加对话框的关闭
    addDialogClosed() {
      this.$refs.addFormRef.resetFields()
    },

    // 点击按钮添加参数
    addParams() {
      this.$refs.addFormRef.validate(async valid => {
        if (valid) {
          let params = {
            id: this.cateId,
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName
          }
          const res = await postCateById(params)
          if (res.meta.status === 201) {
            this.$message.success('添加参数成功')
            this.addDialogVisible = false
            this.getParamsData()
          } else {
            this.$message.error(res.meta.msg)
          }
        }
      })
    },

    // 重置修改的表单
    editDialogClosed() {
      this.$refs.editFormRef.resetFields()
    },

    // 点击按钮修改参数信息
    editParams() {
      this.$refs.editFormRef.validate(async valid => {
        if (valid) {
          let params = {
            id: this.cateId,
            attrId: this.editForm.attr_id,
            attr_name: this.editForm.attr_name,
            attr_sel: this.activeName
          }
          const res = await putCateAttrById(params)
          if (res.meta.status === 200) {
            this.$message.success('修改参数成功')
            this.getParamsData()
            this.editDialogVisible = false
          } else {
            this.$message.error('修改参数失败')
          }
        }
      })
    },

    // 将对 attr_vals 的操作保存到数据库
    async saveAttr_vals(row) {
      // 发起请求保存
      let params = {
        id: this.cateId,
        attrId: row.attr_id,
        attr_name: row.attr_name,
        attr_sel: row.attr_sel,
        attr_vals: row.attr_vals.join(' ')
      }
      const res = await putCateAttrById(params)
      if (res.meta.status === 200) {
        this.$message.success('修改参数项成功')
      } else {
        this.$message.error('修改参数项失败')
      }
    },

    // 获取参数的列表数据
    async getParamsData() {
      // 证明选中的不是三级分类
      if (this.selectCateKeys.length !== 3) {
        this.selectCateKeys = []
        this.manyTabData = []
        this.onlyTabData = []
        return
      }
      // 证明选中的是三级分类
      // 根据所选分类的 id 和当前所处的面板获取对应的参数
      let params = {
        id: this.cateId,
        sel: this.activeName
      }
      const res = await getCateById(params)
      if (res.meta.status === 200) {
        res.data.forEach(item => {
          item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
          // 控制文本框的显示与隐藏
          item.inputVisible = false
          // 文本框中输入的值
          item.inputValue = ''
        })
        if (this.activeName === 'many') {
          this.manyTabData = res.data
        } else {
          this.onlyTabData = res.data
        }
      } else {
        this.$message.error('获取参数列表失败')
      }
    }
  },
  computed: {
    // 如果按钮需要被禁用返回 TRUE，反之。
    isBtnDisabled() {
      if (this.selectCateKeys.length !== 3) {
        return true
      }
      return false
    },
    // 当前选中的三级分类 id
    cateId() {
      if (this.selectCateKeys.length === 3) {
        return this.selectCateKeys[2]
      }
      return null
    },
    // 动态计算标题文本
    titleText() {
      if (this.activeName === 'many') {
        return '动态参数'
      }
      return '静态属性'
    }
  }
}
</script>

<style scoped>
.cat_opt {
  margin: 15px 0;
}
.el-tag {
  margin: 10px;
}
.input-new-tag {
  width: 120px;
}
</style>
